signInWithEmailAndPassword. Getting a NullPointerException

Question

I wanted to start my new and also first app, and it crashes every time i hit the button to login. It tells me that there is a NullPointerException, but i have no clue why. Could someone help me? Have been looking for solutions but can't find any helping ones so far.

package com.glowchat.app;

import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;

public class LoginActivity extends AppCompatActivity {

    private Button loginbtn;
    private EditText email;
    private EditText password;

    private FirebaseAuth auth;
    private FirebaseUser user;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);

        loginbtn = (Button) findViewById(R.id.loginbtn);

        loginbtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                email = (EditText) findViewById(R.id.inputEmailLogin);
                password = (EditText) findViewById(R.id.inputPasswordLogin);

                String loginemail = email.getText().toString();
                String loginpassword = password.getText().toString();

                if (loginemail.isEmpty() || loginpassword.isEmpty()) {
                    Toast.makeText(LoginActivity.this, "Please fill out all fields.", Toast.LENGTH_SHORT).show();
                } else {
                    auth.signInWithEmailAndPassword(loginemail, loginpassword).addOnCompleteListener(LoginActivity.this, new OnCompleteListener<AuthResult>() {
                        @Override
                        public void onComplete(@NonNull Task<AuthResult> task) {
                            if (task.isSuccessful()) {
                                Toast.makeText(LoginActivity.this, "Authentication successfull.", Toast.LENGTH_SHORT).show();
                                user = auth.getCurrentUser();
                            } else {
                                Toast.makeText(LoginActivity.this, "Authentication failed. Check your input and your internet connection.", Toast.LENGTH_SHORT).show();
                                user = null;
                            }
                        }
                    });
                }
            }
            });
    }

}

This is what i get in the Run tab:

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.glowchat.app, PID: 29274
    java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.tasks.Task com.google.firebase.auth.FirebaseAuth.signInWithEmailAndPassword(java.lang.String, java.lang.String)' on a null object reference
        at com.glowchat.app.LoginActivity$1.onClick(LoginActivity.java:47)
        at android.view.View.performClick(View.java:6935)
        at android.widget.TextView.performClick(TextView.java:12742)
        at android.view.View$PerformClick.run(View.java:26211)
        at android.os.Handler.handleCallback(Handler.java:790)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:7000)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:441)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1408)

Dude, you get an red error message in the "run" tab in android studio at the bottom. There you see more information which you can post here. For sure, one of your EditText will have a null pointer I guess...maybe the R.id....are not correct named or present at the layout — user1804084, Apr 27 '19 at 19:28
@user1804084 i edited it. but i am not able to find an error myself. — TheAlexGamer, Apr 27 '19 at 19:35
Hint2: your code never enters the "sign-in" function body, so that's not exactly where it's crashing — OneCricketeer, Apr 27 '19 at 19:38

score 0 · Answer 1 · answered Apr 27 '19 at 19:47

0

You just declared FirebaseAuth auth but not init it so that you can't signInWithEmailAndPassword.

I think this Firebase docs will help you a little bit.

answered Apr 27 '19 at 19:47

rovn

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signInWithEmailAndPassword. Getting a NullPointerException

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